Adding a copyright/license info for skimage/_shared/six.py

debian/copyright

@@ -51,6 +51,9 @@ Files: skimage/morphology/_pnpoly.h
 Copyright: 1970-2003, Wm. Randolph Franklin
 License: BSD-3
 
+Files: skimage/_shared/six.py
+Copyright: 2010-2013, Benjamin Peterson
+License: Expat
 
 License: BSD-3
   Redistribution and use in source and binary forms, with or without
@@ -148,3 +151,22 @@ License: PSF
   8. By copying, installing or otherwise using matplotlib 0.98.3,
   Licensee agrees to be bound by the terms and conditions of this
   License Agreement.
+
+License: Expat
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+ .
+ The above copyright notice and this permission notice shall be included in all
+ copies or substantial portions of the Software.
+ .
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ SOFTWARE.